This is a competitive renewal application for the Cincinnati Rheumatic Diseases Core Center. The Core Center is structured to foster existing interactions, and to encourage new ones, between investigators in pediatric and adult rheumatology divisions, and the broader immunology and bioinformatics communities, with the ultimate goal of improving the outcome for children with rheumatic illness. Members of the research base are investigators whose studies fall into one of five categories: 1) pediatric rheumatic diseases, 2) rheumatic diseases more often seen in adults, 3) developing tools to translate laboratory findings to clinical rheumatological practice, 4) studies involving animal models of rheumatic disease 5) and immunobiological or other basic science studies judged to be of broad relevance to the pathophysiology of rheumatic disease. A number of investigators are involved in research spanning more than one of these categories. The individual core components have evolved to maximize their impact and exploit strong interactions between members of the research base. There are four cores proposed. A Pediatric Rheumatology Tissue Repository, which has played an important role in enhancing studies not only for the local research base but also has extended its utility to the national level. The In Vivo Imaging Core has evolved from the Magnetic Resonance Imaging Core to reflect more comprehensive imaging capabilities, including the addition of a micro CT scanner. In addition to flow cytometry and cell sorting services, the Integrative Cell Phenotyping and Morphology Core has expanded its capabilities to offer pathology services including immunohistochemistry and in situ hybridization analyses. The Rheumatic Diseases Research Informatics Core, instrumental to many investigators, has evolved in parallel with the scope of research projects to provide state of the art support, especially important in the genomic era. The center will also support two highly innovative Pilot and Feasibility (P&F) projects: 1) Modulation of Tissue Inflammation by RP105/TLR4 and 2) Role of Angptl4, an Angiogenic Mediator, in Arthritis.